JPH0374477A - Manufacture of self-crosslinking cationic paint binder - Google Patents

Abstract

PURPOSE: To provide a process for preparing a self-crosslinking cationic coating binder which can be diluted with water after protonation and can yield a coating possessing good solvent resistance and other properties by reacting an aminoalkylation product of a specified phenol with an epoxy resin.

CONSTITUTION: An aminoalkylation product formed from a substd. phenol and an alkylamine or the like and formaldehyde (a donor) is reacted with a diisocyanate with one side being masked. Subsequently, 50 to 100% of the phenolic hydroxyl group is reacted with a diepoxy resin so that 5 to 70 mol.% of the diglycidyl group of the diepoxy resin is reacted, optionally followed by a reaction of the reaction product with a monoamine and a diamine. Thus, a contemplated binder is obtd. which is obtd. from an aminoalkylation product of phenol and an epoxy resin and can be diluted with water after protonation.

COPYRIGHT: (C)1991,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is based on a reaction product formed from an aminoalkylated product of phenols and an epoxy resin, which can be diluted with water after protonation, and which can be diluted with water after protonation. The present invention relates to a method for producing a self-crosslinking cationic paint binder, in which the jepoxy resin used is partially modified with monoamines and diamines.

For a method of producing reaction products formed from aminoalkylated bioacids of phenols and epoxy resins, see Austrian Patent Specification No. 382.160, No. 384,2.
No. 32, No. 384.818, No. 385.048, No. 386.220, No. 386,221 and No. 390,
It has already been described in No. 071.

Austrian Patent Specification No. 382.160 can be diluted with water after protonation and furthermore (1) on average at least 1i! a monoalkylphenol or a monoarylphenol or a monoaralkylphenol containing an NH group of I and having phenol and/or substituted phenol, preferably one or optionally two phenolic hydroxyl groups, and a primary alkylamine and/or or an aminoalkylation product formed from a primary alkanolamine and/or a primary/tertiary alkyl diamine and formaldehyde or a formaldehyde donor;
(3) 50 to 10 of the phenolic hydroxyl groups in the subsequent reaction step.
0% as an epoxy compound, preferably with an epoxy equivalent of 50
A process for producing a self-crosslinking cationic paint binder based on a reaction product formed from an aminoalkylation product of phenol and an epoxy resin, characterized in that the reaction product is reacted with a jepoxy resin of 2,000 to 2,000. It is related to.

In the course of continuing this research, it was determined that the applicability and rheological properties of coatings based on the product of Austrian Patent Specification No. 382,160 were determined by the use of monoamines or diamines in the final stage of the jepoxy resin. We have found that this can be improved by modifying the partial reaction.

That is, the present invention can be diluted with water after protonation and furthermore (1) contains on average fewer (at least one NH group) per molecule and contains phenols and/or substituted phenols, preferably one or a monoalkylphenol or a monoarylphenol or a monoaralkylphenol having two phenolic hydroxyl groups, and a primary alkylamine and/or a primary alkanolamine and/or a primary/tertiary alkyldiamine,
The aminoalkylation product formed from formaldehyde or a formaldehyde donor is reacted with (2) a semi-masked diisocyanate, and in a subsequent reaction step (3) 50 to 100 of the phenolic hydroxyl groups are reacted.
% with an epoxy compound, preferably a jepoxy resin with an epoxy equivalent weight of 50 to 2,000, based on the reaction product formed from an aminoalkylation product of phenol and an epoxy resin. In the method for producing a self-crosslinking cationic paint binder, 5 to 70 mol%, preferably 10 to 40 mol% of the glycidyl groups of the jepoxy resin used in step (3) above.
mol % is reacted with monoamines and diamines before reacting with the intermediate obtained in step (2) or, if necessary, simultaneously when the gepoxy resin is reacted according to step (3). The present invention relates to a characteristic method for producing a paint binder.

Such modification improves the applicability and rheology of the binder and the paint formulated with this binder, as well as the deposited film properties after crosslinking.

The preparation of the precursors and intermediates used in the present invention is described in Austrian Patent Specification No. 382.160
It is carried out according to the method described in No.

The monoamines used for the modification according to the invention can essentially be all primary and secondary amines, such as monoalkyl monoamines or dialkyl monoamine analogs or monoalkanol monoamines or dialkanol monoamine analogs.

The diamine used is preferably the reaction product of a diprimary amine and 2 mol of a monoepoxy compound.

Primary/tertiary diamines such as dimethylamino-propylamine and its congeners can also be used.

Amine-functional compounds used in certain embodiments are described in European Patent Specification No. 0. ．． It is an oxazolidine amine described in No. 076.955 and represented by the following general formula.

and/or a branched alkyl group, or an aryl group or a hydrogen atom, or an alkyl group if necessary, when R3 groups are taken together,
It is an alkylene group forming a ring substituted with an aryl group or an alkoxy group, and R includes an ether or ester group if necessary.
A saturated or unsaturated aliphatic or cycloaliphatic or aromatic hydrocarbon.

R4 is a hydrogen atom or a CHa group, and n is 2 to 4
and/or in the formula, R1 is a linear, branched or cyclic alkylene group or aralkylene group having 2 to 12 carbon atoms, and R2 is a line having 1 to 4 carbon atoms. R5 is the group remaining after the monofunctional acrylic or methacrylic monomer with respect to the double bond reacts with the active hydrogen atom, and R6 is a hydrogen atom or an alkyl group. .

The reaction of the jepoxy or polyepoxy compound with the amine is carried out either before or simultaneously with the reaction of the epoxy compound and the phenolic component. In each case the reaction is carried out at 60 DEG to 100 DEG C., but the proportions used and the reaction conditions are chosen such that the final product does not contain free epoxy groups. No clear difference could be made between the final products produced by these two methods.

In order to impart dilutability with water, the basic groups of the reaction product are partially or completely neutralized with an acid, preferably formic acid, acetic acid or lactic acid.

Practical dilutability is usually obtained by neutralizing 20 to 60% of the basic groups or by using approximately 20 to 60 mmol of acid per 100 g of solid resin. The binder is then diluted with deionized water to the desired concentration. If necessary, process with crosslinking catalysts, pigments, fillers, and other additives before neutralization, or before dilution, or in partially diluted form.

Can be made into colored paint.

The formulation of such coatings and their application in electrocoating processes are known to those skilled in the art and are described in the literature. The hardening of the deposited coating film when used as a primer was 15%.
It is carried out at a temperature of 0 to 170°C for 10 to 30 minutes.

If the binder does not contain sufficient self-crosslinking structures, additional crosslinking agents such as masked isocyanates or amino or phenolic resins can be used.

If properly formulated, the products of the invention can also be applied by other methods such as dip coating, roller coating or spray coating. If necessary, the binder of the present invention can also be processed with an organic solvent.

The following examples are intended to illustrate the invention:
Unless otherwise specified, the present invention is not limited to the following:
Parts or percentages are by weight.

The following abbreviations are used in the examples.

PH phenol NPH nonylphenol BPA Bisphenol A DMAPA N,N-dimethylaminopropylamine DEAPA N,N-diethylaminopropylamine ERA 2-ethylhexylamine EGL
Monoethyl glycol monoethyl ether MICI Half-masked tolylene diisocyanate MICn by EGL Half-masked tolylene diisocyanate EPHI by 2-ethylhexanol Jepoxy resin based on bisphenol A (epoxy equivalent weight approx. 190) EPHn EPHII OXAM I OXAM n IAM Gepoxy resin based on bisphenol A (epoxy equivalent: approx. 480) Glycidyl ether of tertiary C,/C, monocarboxylic acid (epoxy equivalent: approx. 250) Aminoethylethanolamino 1 mole, acrylic acid 2, monoethylhexyl 1 Oxazolidine amine formed from 1 mole of diethylenetriamine, 2 moles of octene oxide and 2 moles of formaldehyde (molecular weight = 231) Reaction of 1 mole of pentamethylenediamine with 2 moles of EPHm Product (molecular weight = 602) DOLA Jetanolamine DGDM
Diethylene glycol dimethyl ether MOP Methoxypropanol modified alkylaminated products [modified products (VP) 1-4] were prepared according to the examples of Austrian Patent Specification No. 382.160 in the proportions shown in Table 1.

It can be prepared using either a one-stage process or a two-stage process using the starting materials shown in Table 2. It was not possible to make clear differences of more than 1 normal variation in the properties of the products.

In the one-stage method, the components are made into a 70% solution in the solvent shown in Table 2, and the mixture is heated at 95 to 100% until the epoxy groups are completely reacted.
React at ℃. When a monoglycidyl compound is used, preferably it does not react until the reaction between the jepoxy resin and the amine compound is completed.

In the two-step method, a jepoxy resin and an amine compound are reacted until epoxy groups corresponding to the theoretical amount of amino hydrogen react with each other.
The first stage reaction is carried out at 60 to 80°C between a modified aminoalkylated product (modified product) and a monoglycidyl compound (
(if used) and reduce the solids content to 70~70% with solvent.
After adjusting to 75%, the reaction is further carried out at 90-100°C until the epoxy value becomes almost zero.

For further processing of the product, the solids content of the product is adjusted as shown in Table 2. As the solvent used, glycol ethers are suitable, and methoxypropanol is preferable.

The "Solubility" column shows the amount of formic acid (mmol) per 100 g of resin solids required to obtain a stable transparent lacquer when diluted with water to a solids content of 15%.

The binders prepared in Examples 1 to 6 were deposited by electrical means on steel plates in the form of transparent lacquers. The transparent lacquer was prepared by adding dibutyltin dilaurate in an amount corresponding to 0.8% of the metal to the resin solution obtained in the example (based on resin solids) and the resulting mixture was diluted with deionized water. It was diluted to a solid content of 15%. The coating film is 1
It was baked at 60°C for 20 minutes. It had a methyl ethyl ketone resistance of at least 150 reciprocating rubs at a coating thickness of 20±2 μm.

Claims (1)

[Claims] 1. Can be diluted with water after protonation, and further contains (1) on average at least one NH group per molecule, and phenol and/or substituted phenol, preferably one or A monoalkylphenol or monoarylphenol or monoaralkylphenol optionally having two phenolic hydroxyl groups, a primary alkylamine and/or a primary alkanolamine and/or a primary/tertiary alkyldiamine, The aminoalkylated product formed from formaldehyde or a formaldehyde donor is reacted with (2) a semi-masked diisocyanate, and in a subsequent reaction step (3) 50 to 100% of the phenolic hydroxyl groups are removed.
based on the reaction product formed from the aminoalkylation product of phenol and the epoxy resin, obtained by reacting the phenol with an epoxy compound, preferably a diepoxy resin having an epoxy equivalent weight of 50 to 2,000. In the method for producing a self-crosslinking cationic paint binder, 5 to 70 mol%, preferably 10 to 40 mol% of the glycidyl groups of the diepoxy resin used in step (3) above.
mol % with monoamines and diamines before reacting with the intermediate obtained in step (2) or, if necessary, simultaneously when the diepoxy resin is reacted according to step (3). Characteristic paint binder manufacturing method. 2. The method for producing a paint binder according to claim 1, wherein the monoamines used are primary and secondary amines. 3. The method for producing a paint binder according to claim 1, wherein the monoamines used are primary and secondary alkanolamines. 4. The method for producing a paint binder according to claim 1, wherein the diamine used is a reaction product of a diprimary amine and 2 moles of a monoepoxy compound. 5. The method for producing a paint binder according to claim 1, wherein the diamine used is a primary-tertiary diamine. 6. The functional compound used has a general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I) and/or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) and/or ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (III) (wherein R_1 is a linear, branched or cyclic alkylene group having 2 to 12 carbon atoms or an aralkylene group, and R_2 is a carbon number of 1 to 4 Linear or branched alkyl group, or aryl group, hydrogen atom, or R_2
The groups together form an alkylene group optionally substituted with an alkyl group, an aryl group, or an alkoxy group, and R_3 is a saturated or It is an unsaturated aliphatic, cycloaliphatic, or aromatic hydrocarbon, R_4 is a hydrogen atom or CH_2 group, n is 2 to 4, and X is a ▲ mathematical formula, chemical formula, table, etc. Either ▼ or ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R_5 is the group that remains after a monofunctional acrylic or methacrylic monomer reacts with an active hydrogen atom regarding the double bond, The method for producing a paint binder according to claim 1, wherein R_6 is an oxazolidine amine represented by a hydrogen atom or an alkyl group.